The confusion is getting worst confounded. If a father dies intestate (without having written a WILL) all his sons and daughters and wife have equal share in the property left behind by him (either self acquired or inherited by him from his forefathers).
You don't have a share. Your wife has. There is only way to get it and the best way is for all the legal heirs to agree mutually and apply for succession certificate which makes entitled to their share legally.
Since it is a matter of property (where most of the families have been destroyed), the other way is also to apply for succession certificate and fight the battle ferociously in a court of law.
The worst scenario would be when the brother disowns her sister and vice versa. You should be prepared, if not done in a gentlemanly way, to have a bitter battle for God's knows how many years and at what cost.
The soon your wife's files for her claim the better. Nobody has seen tomorrow.